Uganda biotech law opens door to disease-resistant GMO crops

Monday, October 9, 2017

By Joan Conrow and Mark Lynas

Bananas, an important food crop, are sold at a market in Uganda. Photo by Joan Conrow

Genetically engineered crops that promise to benefit both farmers and consumers are poised to enter Uganda’s marketplace now that its Parliament has adopted a law to regulate agricultural biotechnology.

Ugandan plant scientists are already in the later stages of conducting field trials for banana varieties that are resistant to diseases and can deliver improved content of the vital micronutrient Vitamin A.

Ugandans consider cooked green banana — called matoke — a staple crop, consuming about a kilogram (2.2 pounds) a day on average, with banana comprising 30 to 60 percent of daily calorific intake throughout the whole East African region.

Though the market for their produce is strong, Uganda’s banana farmers increasingly are suffering losses due to devastating plant diseases such as banana bacterial wilt (BBW), which can topple a healthy plantation literally overnight.

Meanwhile, many of Uganda’s poorest children are suffering from micronutrient deficiencies that impair their health, most notably a shortage of vitamin A that can result in blindness.

Public sector scientists working with the support of international donors have identified genetic engineering solutions to these problems, breeding matoke varieties that are disease-resistant and fortified with vitamin A. They have been patiently tending their research crops while waiting for the government to adopt a process that will allow farmers to begin growing these new varieties. With Parliament’s action last week, it appears their labors will soon bear fruit.

Dr. Priver Namanya at her banana field trials in Kawanda. Photo by Sarah Evanega

“It is generally agreed that improving a staple crop is the most feasible way to get micronutrients to people,” said Dr. Priver Namanya, head of the banana biofortification project at National Agricultural Research Laboratories (NARL) in Kawanda. “About 30 percent of children under 5 have a vitamin A deficiency. The highest percentage is the western region where bananas are grown.”

Vitamin A deficiency mostly occurs in developing countries where people consume starchy foods such as cooking bananas, cassava, maize and rice as their main source of calories. It is the leading preventable cause of blindness among children, and also — by impairing the immune system — increases the risk of death from common infectious diseases among those under the age of 5.

More nutritious foods such as eggs, meat and fruits are good sources of vitamin A, but these are often expensive, scarce or unavailable to the very poor. Bananas do contain some Vitamin A, but the levels are low in the varieties traditionally grown in Uganda. Dr. Namanya, a tissue culture expert, discovered how to introduce genes extracted from an Asian banana known as Asupina and the African yellow maize to boost the vitamin A content in matoke.

In Uganda, Dr. Namanya’s vitamin A-biofortified bananas have already proven successful in confined field trials, and the passage of the Biosafety Act will now allow her team to move on to multi-locational field trials in different areas of the country in partnership with local farmers.

People like the deep orange color of the fortified banana, she said, and the vitamin A also makes it softer, which adds to consumer appeal. Feeding and nutrition studies still must be conducted, but Namanya is optimistic that the fortified banana she has been working on for the past 13 years will finally be released to farmers by 2021. “I think it will eventually reach its intended beneficiaries — the children and pregnant women,” she said.

Meanwhile, research is also well advanced in Uganda on matoke resistant to banana bacterial wilt (BBW), the top banana-killer disease in the Great Lakes region. NARO scientists have used genetic engineering to extract resistance genes from green pepper and introduce them into the popular M-9 hybrid variety.

These introduced genes have proven successful in conferring 100 percent resistance in some genetically engineered lines of matoke banana. Several years of confined field trials have already been conducted, and the new Biosafety Act will make it possible for scientists to move on to the next stage of conducting further trials around the country. They are also looking at the potential for “stacking” disease-resistance genes with vitamin A.

Joshua Himbisa is a banana farmer in Uganda’s Mbarara district who is eager to try a resistant variety after battling the devastation caused by BBW for several years now.

After retiring from a career as an agriculturalist, he developed a seven-acre banana plantation, anticipating the regular income that such a crop can provide. Farmers appreciate banana because it can be harvested every two weeks, ensuring a steady cash flow. For a few years, profits were good.

“But all of a sudden the BBW thing came,” Himbisa said. “It started slowly killing everything.” Though his banana revenue dropped to almost nothing, “we didn’t lose hope.”

Instead he has engaged in aggressive sanitation measures that include surveying his plantation twice daily and cutting down and burying diseased trees. He and his workers now carefully clean their tools with fire or bleach to ensure they don’t transfer the disease to uninfected trees.

Joshua Himbisa prepares to sterlize a machete after his worker cut down an infected tree. Photo by Sarah Evanega

These measures are never entirely successful in stopping the disease, however. As he spoke, Himbisa noticed a young banana tree on his plantation that was already showing signs of wilting. On his instructions, a worker hacked it down with a machete and buried it in a pit, before starting a small fire nearby to then sterilize his cutting tools.

Himbisa and his wife also have further diversified their farm to include coffee, pumpkin and dairy animals. “If this disease hadn’t come in, I think I would have had a very good retirement,” he said. Yet he still wants to grow banana, and is receptive to trying a disease-resistant genetically engineered variety when it comes available. “As long as the market can accept it, I certainly wouldn’t mind growing it.”

Studies show that about 80 percent of farmers are willing to consume GMOs, though for residents of urban areas, that figure drops to just 30 percent due to the influence of anti-GMO groups. “All the resistance is coming from urban areas. It will be well-received by people in rural areas,” says Patricia Nanteza, a science communication specialist at NARL Kawanda.

Vicent Mugabi, an agricultural extension officer in charge of Mbarara municipality, said that some farmers are fearful of genetic engineering because they are being told the technology will replace their indigenous plants. But he believes they will welcome the GE banana varieties because of their disease resistant traits.

“Our farmers actually will come to accept that idea very much,” Mugabi said. “Farmers ever ask, how far have you gone with this? They look at it as something that is improved.” Plant scientists like Dr. Namanya make clear that both vitamin A and BBW-resistance genes have been introduced to existing farmer-preferred varieties, thereby safeguarding their future in Ugandan agriculture.

Mugabi and Dr. Namanya both agree that the country’s farmers should be given the chance to make informed choices about whether to grow improved crops, and that farmers’ decisions should guide future research work.

With the passage of the long-delayed Biosafety law, small farmers can be more closely involved in the development of improved varieties of staple crops, which will no longer have to be grown exclusively behind high fences and locked gates far away from their intended beneficiaries.